Security - Intruder Alarms

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Physical protections form the vital basis of premises security. However, given sufficient time determined criminals can overcome most physical defences; an intruder alarm is designed to support robust physical security by quickly detecting intruders on the premises, and then by alerting an approved alarm receiving centre (ARC) to enable them to make an appropriate response.

Protective switches are usually fitted to external doors around the perimeter of the building to detect entry by intruders, supplemented by internal trap protection using movement detectors; these devices operate by detecting infra-red energy, and therefore it important that they are not obscured. There is a wide range of detection devices available to protect specific or high security environments, such as vibration detectors, break-glass detectors and hold-up alarms.

It is essential that the intruder alarm system is reliable, and resilient against attack or interference; the correct design, installation, maintenance and operation of the system are therefore vital. The intruder alarm should be set whenever the premises are unoccupied.

Managing the Risk

Design and Installation: should be carried out by alarm companies which are Gold accredited by the National Security Inspectorate (NSI). Such companies must submit themselves for audit against the above standards for design, installation, maintenance and monitoring, together with financial stability an administration, staff vetting and training.

Police Security System Policy (SSP): due to the continuing high levels of false alarm calls received by the police, strict rules have been set out by the National Police Chief Council (NPCC) and applied by all police
forces. Broadly, 3 false calls (2 false calls in respect of personal attack signals) within a 12 month period will result in withdrawal of police response until such time as the system is upgraded and proves itself to be free of false alarm problems. Insurers must be notified if police response is downgraded or withdrawn, and this can have serious implications on premium levels and/or the level of insurance cover provided.

Confirmation Alarm Systems: in order to obtain a police response, new alarm systems must be able to provide confirmed alarm activations; this means that a second alarm signal must be received by the ARC within a specified time period in order for them to summon the police. Compliance with the above standards will satisfy this requirement.

System Notification: upon activation, the system will signal to an approved alarm receiving centre (ARC) via monitored telephone line and radio communication equipment. The ARC will, subject to the Police SSP as above, alert the police to attend the premises, and advise the keyholder. In the event of an unconfirmed activation, the ARC will only advise the keyholder. It is desirable to appoint a ‘first response’ company to attend – the company should be Gold accredited by the National Security Inspectorate (NSI) and their staff should hold individual Security Industry Authority (SIA) licences.

Maintenance: to ensure that the system is maintained in good working order, and to reduce the possibilities of false alarms, the system should be checked at least twice per year by a National Security Inspectorate (NSI) Gold approved installer as apart of a maintenance contract.

Staff Training: employees who are required to set/unset the alarm system should be thoroughly trained in the use of the system – this will assist in reducing the possibilities of false alarms, and will ensure that the
alarm protection is maximised.

Specification Approval: the minimum standard required by AIG Europe Limited is Grade 3 equipment and Grade 4 notification, having a dual path monitored scheme such as BT RedCare and GSM, to an approved alarm receiving centre (ARC). The system should be installed and maintained by a National Security Inspectorate (NSI) Gold category approved company. The design specification for the system, provided by the installing engineers, should be forwarded to AIG Europe Limited for approval, prior to a contract being signed.

Standards: The references are:

  • PD6662 – Scheme of Implementation of European Standards.
  • European Standard EN 50131 – General Requirements.
  • European Standard EN 50136 – Signalling Systems.
  • DD243 – Code of Practice for Confirmation Alarms.
  • BS5979 – Code of Practice for Remote Receiving Centres for Alarm & CCTV.
  • BS7984 – Code of Practice for Keyholding and Response Services.
  • Accreditation by the National Security Inspectorate (NSI) for intruder alarm operations indicates compliance with the above standards.

Solution Supplier

National Security Inspectorate (NSI) is an independent approvals and inspection body for intruder alarms.

For further information please contact your local AIG risk engineer.

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